CN114517085B - Ultralow surface tension foam discharging agent and preparation method thereof - Google Patents
Ultralow surface tension foam discharging agent and preparation method thereof Download PDFInfo
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- CN114517085B CN114517085B CN202210242179.6A CN202210242179A CN114517085B CN 114517085 B CN114517085 B CN 114517085B CN 202210242179 A CN202210242179 A CN 202210242179A CN 114517085 B CN114517085 B CN 114517085B
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
- C09K8/584—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids characterised by the use of specific surfactants
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/70—Combining sequestration of CO2 and exploitation of hydrocarbons by injecting CO2 or carbonated water in oil wells
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Abstract
The invention discloses an ultralow surface tension foam discharging agent and a preparation method thereof. The ultra-low surface tension foam discharging agent comprises the following components in parts by mass: 20-40 parts of gemini dodecyl dimethyl hydroxypropyl sulfobetaine, 0.1-1 part of perfluor nonene oxybenzene sodium sulfonate, 1-4 parts of coconut fatty acid monoethanolamide and 59-79 parts of water. The gemini dimethyl hydroxypropyl sulfobetaine is a gemini surfactant obtained by substituting hydroxyl in dodecyl dimethyl hydroxypropyl sulfobetaine with 1,4 dibromobutane. The ultra-low surface tension foam drainage agent can further improve the oil gas recovery ratio of an ultra-low-yield well, solves the problems of flooding, yield reduction and the like when the capacity of a gas well is extremely low in the later period of gas well exploitation, and meets the foam drainage process requirements of the ultra-low-yield well (below 3000m < 3 >/d).
Description
Technical Field
The invention belongs to the field of foam drainage in oil and gas exploitation, and particularly relates to a foam drainage agent and a preparation method thereof.
Background
The foam drainage gas production of a gas well is a common drainage gas production process in the middle and later stages of natural gas well exploitation. The process mainly uses the foam discharging agent to greatly reduce the density of the accumulated liquid after the underground accumulated liquid is foamed, and simultaneously changes the surface property of the accumulated liquid, thereby reducing the difficulty of discharging the accumulated liquid from the underground.
According to a Turner critical fluid carrying flow rate calculation formula, the reduction of the surface tension can reduce the critical fluid carrying flow rate of the gas well, so that the gas well can carry out the downhole fluid under the condition of lower yield. Currently, the surface tension of common foam discharging agents such as low-pressure low-yield foam discharging agents is usually above 28 mN/m. The addition of fluorocarbon surfactants tends to further reduce the surface tension, but in many cases, the further reduction in the surface tension is affected by the molecular type and the hydrophilicity thereof, which is accompanied by a simultaneous reduction in the foaming performance, foam stabilizing performance, and liquid carrying performance.
At present, a foam discharging agent with a surface tension lower than 24mN/m is still blank. Similar agents with ultralow surface tension performance, such as a cleanup additive, a foaming agent for fracturing and the like, have poor gas well adaptability in the foam drainage gas production process, such as poor mineralization resistance, oil resistance, foam stabilizing performance and the like, and do not have the capability of being directly applied to the foam drainage gas production process of a gas well, although the surface tension can be below 24 mM/m. The existing similar functional medicament is mainly foaming agent for low-pressure low-yield wells, the medicament only pays attention to the performances such as foam stabilization, foam density and the like, but the surface tension cannot be improved greatly, the similar functional medicament has certain advantages in common low-pressure low-yield wells (the bottom hole flow pressure is below 10Mpa, the yield is 3000m3/d to 8000m 3/d), the foam discharging efficiency improvement is not obvious in ultra-low-yield gas wells (below 3000m 3/d), the foam discharging process adaptability is obviously insufficient, and the foam discharging effect is ensured by auxiliary measures such as emptying liquid, gas lifting liquid and the like. The ultra-low production well foam-removing process has higher requirements on the low surface tension of the foam removing agent.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides an ultralow surface tension foam drainage agent and a preparation method thereof, so as to further improve the oil and gas recovery ratio of an ultralow-yield well, solve the problems of flooding, yield reduction and the like when the productivity of the gas well is extremely low in the later period of gas well exploitation, and meet the foam drainage process requirements of the ultralow-yield well (below 3000m < 3 >/d).
The invention provides an ultralow surface tension foam discharging agent which comprises the following components in parts by mass:
the ultra-low surface tension foam discharging agent is further characterized in that the gemini dodecyl dimethyl hydroxypropyl sulfobetaine is a gemini surfactant obtained by substituting hydroxyl groups in dodecyl dimethyl hydroxypropyl sulfobetaine by 1,4 dibromobutane.
The preparation method of the ultralow surface tension foam discharging agent provided by the invention comprises the following steps:
according to the component proportion of the ultra-low surface tension foam discharging agent, adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle, keeping the temperature to 65-75 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring for 1h, cooling, and stopping stirring to obtain the product.
In the ultra-low surface tension foam drainage agent and the preparation method thereof, the dodecyl dimethyl hydroxypropyl sulfobetaine is prepared by the following method:
mixing dodecyl dimethyl hydroxypropyl sulfobetaine and ethylene glycol dimethyl ether, stirring at 55-65 ℃ until the mixture is uniform, keeping stirring, adding NaOH solution, heating to 75-85 ℃, dropwise adding 1, 4-dibromobutane, and continuously stirring for reaction for 6-8 h, wherein the molar ratio of the dodecyl dimethyl hydroxypropyl sulfobetaine to the 1, 4-dibromopropane is (1.95-2.05): 1, a step of; after the reaction is finished, removing ethylene glycol dimethyl ether and unreacted 1, 4-dibromobutane, dissolving with ethanol, filtering to remove unreacted NaOH, removing ethanol, crystallizing with acetone for 2-3 times, and vacuum drying to obtain white solid, namely the gemini dimethyl hydroxypropyl sulfobetaine.
Further, the mass percentage concentration of the NaOH solution is 49-51%, and the mass dosage of the NaOH solution is 50-70% of the mass of the dodecyl dimethyl hydroxypropyl sulfobetaine.
Further, the mass dosage of the ethylene glycol dimethyl ether is 6-8 times of the mass of the dodecyl dimethyl hydroxypropyl sulfobetaine.
Compared with the prior art, the invention has the following beneficial effects:
1. the foam discharging agent has the advantages of low surface tension, strong foaming capacity, good foam stabilizing effect, strong liquid carrying capacity and excellent performance, can effectively reduce the surface tension of accumulated liquid, further reduce critical liquid carrying flow rate, obviously increase the adaptability of a low-yield well of a foam discharging and gas production process, and further help to improve the gas production rate.
2. In the formula of the foam discharging agent, the gemini dodecyl dimethyl hydroxypropyl sulfobetaine is a main component, the perfluoro nonene oxybenzene sodium sulfonate can further reduce the surface tension of the product, meanwhile, the foam efficiency of the product is improved, the coconut fatty acid monoethanolamide has obvious improvement effect on the foam stability, and the components are synergistic to obtain the effects of ultralow surface tension, strong foaming capacity, good foam stabilizing effect and strong liquid carrying capacity of the foam discharging agent.
Detailed Description
The invention is further illustrated by the following examples. It is to be noted that the following examples are given solely for the purpose of illustration and are not to be construed as limitations on the scope of the invention, since numerous insubstantial modifications and variations of the invention will become apparent to those skilled in the art in light of the above disclosure, and yet remain within the scope of the invention.
Example 1
The ultra-low surface tension foam discharging agent provided by the embodiment comprises the following components in parts by mass:
the preparation method comprises the following steps:
adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle according to the component proportion of the ultralow surface tension foam discharging agent, keeping the temperature to 70 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring for 1h, cooling, and stopping stirring to obtain the product.
The preparation method of the gemini dodecyl dimethyl hydroxypropyl sulfobetaine comprises the following steps:
16.84g (0.048 mol) of dodecyl dimethyl hydroxypropyl sulfobetaine was mixed with 120mL of ethylene glycol dimethyl ether, and the mixture was poured into a 250mL three-necked flask equipped with a stirrer and a condenser. Stirring at 60℃and 250r/min until homogeneous, adding 10mL of 50% by mass NaOH solution, heating to 80℃and slowly adding 5.18g (0.024 mol) of 1, 4-dibromobutane (about 0.5 h) with stirring using a constant pressure dropping funnel, and continuing the reaction for 7h. After the reaction was completed, it was transferred to a single-necked round bottom flask, ethylene glycol dimethyl ether and unreacted 1, 4-dibromobutane were removed by distillation under reduced pressure, then unreacted NaOH was removed by filtration while it was still hot by dissolving with 60mL of ethanol, ethanol was further distilled off, and the product was recrystallized 3 times with acetone and dried under vacuum for 24 hours to give white solid, gemini dimethyl hydroxypropyl sulfobetaine.
The other component materials in this example were all commercially available.
Comparative example 1
The same formulation amount and the same method were used to prepare a foam discharging agent by replacing gemini dodecyl dimethyl hydroxypropyl sulfobetaine in example 1 with dodecyl dimethyl hydroxypropyl sulfobetaine.
Example 2
The preparation method comprises the following steps:
adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle according to the component proportion of the ultralow surface tension foam discharging agent, keeping the temperature to 65 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring for 1h, cooling, and stopping stirring to obtain the product.
In this example and the following examples, the preparation method of gemini dodecyl dimethyl hydroxypropyl sulfobetaine was the same as in example 1.
Example 3
The preparation method comprises the following steps:
adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle according to the component proportion of the ultralow surface tension foam discharging agent, keeping the temperature to 75 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring for 1h, cooling, and stopping stirring to obtain the product.
Example 4
The preparation method comprises the following steps:
adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle according to the component proportion of the ultralow surface tension foam discharging agent, keeping the temperature to 75 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring for 1h, cooling, and stopping stirring to obtain the product.
The ultra-low surface tension foam blowing agent prepared in example 1 was subjected to the following performance test and comparison.
1) Surface tension test
Mineralized water: the mineralized water contains 40g/L of sodium chloride, 8g/L of calcium chloride and 2g/L of magnesium chloride.
The testing method comprises the following steps: preparing an ultralow surface tension foam drainage agent prepared in the example 1 and mineralized water into an aqueous solution with the mass concentration of 0.5%; taking 250ml of prepared aqueous solution, and carrying out surface tension test by adopting a circular ring method under the conditions of 30 ℃ and normal pressure; the foam discharging agent was also measured as a conventional foam discharging agent of comparative example 1, commercially available from a certain company, and as a low-pressure low-yield foam discharging agent of a certain company. The measurement results are shown in Table 1.
TABLE 1
2) Determination of foaming Effect
Mineralized water: the mineralized water contains 40g/L of sodium chloride, 8g/L of calcium chloride and 2g/L of magnesium chloride.
The testing method comprises the following steps: preparing an ultralow surface tension foam drainage agent prepared in the embodiment 1 and mineralized water into an aqueous solution with the mass concentration of 0.5%; 250ml of the prepared aqueous solution was used for the Roche foam test at 80℃under normal pressure, and the foam height were measured for 10 minutes. The foam discharging agent was also measured in comparative example 1, a conventional foam discharging agent of a commercial company and a low pressure foam discharging agent of a commercial company, and the measurement results are shown in Table 2.
TABLE 2
3) Liquid carrying efficacy measurement
Mineralized water: the mineralized water contains 40g/L of sodium chloride, 8g/L of calcium chloride and 2g/L of magnesium chloride.
The testing method comprises the following steps: preparing an ultralow surface tension foam discharging agent prepared in the embodiment 1 into a 0.5% aqueous solution with mineralized water; taking 250ml of prepared aqueous solution, and measuring the liquid carrying amount under the conditions of 80 ℃ and normal pressure: closing the cock at the lower end of the Roche foam apparatus, pouring the solution into the Roche foam apparatus, connecting a liquid collecting pipe, connecting the liquid collecting pipe to a 2L measuring cup, introducing 5L/min air flow for foaming, carrying out liquid for 15min, collecting the liquid carried out in 15min, and metering to obtain liquid carrying amount;
the foam discharging agent was also measured in comparative example 1, a conventional foam discharging agent commercially available from a company, and a low-pressure low-yield foam discharging agent from a company, and the measurement results are shown in Table 3.
TABLE 3 Table 3
4) On-site application effects
The foam discharging agent prepared in example 1 was subjected to a field application test. Diluting the ultra-low surface tension according to the volume ratio of the ultra-low surface tension to the configuration water of 1:8 for standby. The well casing pressure is 1.8Mpa, the oil pressure is 1Mpa, the oil casing pressure difference is 0.8Mpa, and the gas yield is 2700m 3 /d, water yield 0.5m 3 And/d, the original medicament used in the foam discharging process is the conventional foam discharging agent sold in the market, and the adding amount is 8L/d. After the ultra-low surface tension foam discharging agent is used, the dosage of the agent is kept unchanged at 8L/d, the gas well casing pressure is reduced to 1.7Mpa, the oil pressure is increased to 1.1Mpa, the oil casing pressure difference is reduced to 0.6Mpa, and the gas yield is increased to 3500m 3 And/d, the water yield rises to 0.8m 3 And/d, test conditions are shown in Table 4.
TABLE 4 Table 4
The test shows that the foam discharging agent has lower surface tension, better foaming capacity, foam stabilizing effect and liquid carrying capacity, and can meet the high requirement of low surface tension of the foam discharging agent in an ultralow-yield gas well (less than 3000m < 3 >/d), so that the adaptability of the foam discharging and gas production process to low-yield wells is obviously improved.
Claims (2)
1. The foam discharging agent with the ultra-low surface tension is characterized by comprising the following components in parts by mass:
20-40 parts of gemini dodecyl dimethyl hydroxypropyl sulfobetaine
0.1-1 part of perfluorononene oxy benzene sulfonic acid sodium salt
Coconut oil fatty acid monoethanolamide 1-4 parts
59-79 parts of water
The gemini dodecyl dimethyl hydroxypropyl sulfobetaine is prepared by the following method:
mixing dodecyl dimethyl hydroxypropyl sulfobetaine and ethylene glycol dimethyl ether, stirring at 55-65 ℃ until the mixture is uniform, keeping stirring, adding NaOH solution, heating to 75-85 ℃, dropwise adding 1, 4-dibromobutane, and continuously stirring for reaction for 6-8 hours, wherein the molar ratio of the dodecyl dimethyl hydroxypropyl sulfobetaine to the 1, 4-dibromobutane is (1.95-2.05): 1, a step of; after the reaction is finished, removing ethylene glycol dimethyl ether and unreacted 1, 4-dibromobutane, dissolving with ethanol, filtering, removing ethanol again, crystallizing with acetone for 2-3 times, and vacuum drying to obtain white solid, namely the gemini dodecyl dimethyl hydroxypropyl sulfobetaine;
the mass percentage concentration of the NaOH solution is 49-51%, and the mass consumption of the NaOH solution is 50-70% of the mass of the dodecyl dimethyl hydroxypropyl sulfobetaine;
the mass dosage of the ethylene glycol dimethyl ether is 6-8 times of the mass of the dodecyl dimethyl hydroxypropyl sulfobetaine.
2. The method for preparing the ultra-low surface tension foam discharging agent as claimed in claim 1, which is characterized by comprising the following steps:
according to the component proportion of the ultralow surface tension foam discharging agent, adding water and gemini dodecyl dimethyl hydroxypropyl sulfobetaine into a reaction kettle, keeping the temperature to 65-75 ℃, adding sodium perfluor nonenoxybenzene sulfonate and coconut fatty acid monoethanolamide under stirring, continuing stirring, cooling, and stopping stirring to obtain the foam discharging agent.
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| CN105154053A (en) * | 2015-09-29 | 2015-12-16 | 中国石油天然气股份有限公司 | Foam scrubbing agent and preparation method and application thereof |
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| CN105542741B (en) * | 2016-01-19 | 2018-11-16 | 长江大学 | Heatproof foam stabilizing type low interfacial tension foaming agent and preparation method thereof |
| CN106986796B (en) * | 2017-05-24 | 2019-03-26 | 陕西科技大学 | A kind of Gemini surface active agent and its preparation method and application |
| CN111218267B (en) * | 2020-01-19 | 2022-05-13 | 成都华阳兴华化工有限公司 | Foam scrubbing agent with low foam water content and preparation method thereof |
| CN113684014A (en) * | 2021-09-23 | 2021-11-23 | 扬州润达油田化学剂有限公司 | Fluorocarbon gemini anti-oil-foam discharging agent and preparation method thereof |
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| CN105154053A (en) * | 2015-09-29 | 2015-12-16 | 中国石油天然气股份有限公司 | Foam scrubbing agent and preparation method and application thereof |
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